The South African vocalist who contributed to The Lion King’s soundtrack was Lebo M.
Born Lebohang Morake in Soweto, Johannesburg, Lebo M became closely associated with the film’s African vocal sound. He provided vocal arranging, background vocals, co-lead vocals, and African chant work on the original soundtrack, helping give the music a distinctive choral and South African character.
Composer Hans Zimmer recommended him to Disney after working with him on The Power of One. Lebo M helped form and conduct the African choir heard in The Lion King, and his vocal presence is especially associated with the opening “Circle of Life.” He also contributed to later Lion King music, including Rhythm of the Pride Lands.
The other options describe different roles: Tim Rice wrote lyrics, Elton John composed and performed songs, and Hans Zimmer composed the film score. Lebo M was the soundtrack’s key South African vocal contributor.